超高分子量聚乙烯纤维/碳纤维混杂轻质复合材料结构件的研制

【作者】 何洋；

【导师】 梁国正；

【作者基本信息】 西北工业大学 ， 材料学， 2004， 硕士

【摘要】 论文针对超高分子量聚乙烯（UHMWPE）纤维粘接性差，没有合适的既能与之获的良好粘接界面又可以获得良好结构强度的树脂基体的问题，展开了纤维表面的铬酸氧化处理、合成VE树脂以及采用碳纤维进行混杂三种途径的研究。 在纤维的表面处理部分，研究了不同配方以及处理工艺参数的铬酸体系的氧化效果，确定最佳配方方K₂Cr₂O₇∶H₂O：H₂SO₄为10∶16∶140，最佳处理温度为85℃，处理速度为6cm／s；借助于FTIR、SEM等分析手段对处理机理以及处理后纤维表面形貌进行了表征：通过自制的单丝拔出实验装置对处理前后纤维的粘接性进行了测试，发现铬酸对UHMWPE纤维的表面处理具有很好的效果，DC88的处理效果比DC85好，处理后的纤维表面形成了羟基、羧基等极性基团。氧化作用较容易发生在非晶区。 在VE树脂的合成及表征部分，研究确定了反应的最佳物料配比以及反应条件，对合成机理以及影响因素进行了探讨；借助于FTIR、DMA、DTA、TGA、SEM等测试分析手段对树脂的性能进行了表征。发现VEⅠ的热性能以及力学性能要好于VEⅡ，两种树脂相对E-51环氧树脂来说，均具有良好的粘接性，且两种树脂对UHMWPE纤维的粘接性比较接近。 在混杂实验部分，研究了纤维状况（纤维种类、处理与未处理）、混杂方式、含胶量等对混杂结果的影响；借助于SEM以及建立的混杂模型对混杂机理进行了分析；对混杂复合材料进行了密度和耐湿热性测试。研究表明采用处理后的DC88纤维，选择VEⅡ作为基体采用层间混杂的方式，在控制含胶量在40wt％时得到的单向纤维布的粘接性是未处理纤维与E-51环氧树脂的5倍；层间混杂的效果比层内好；纤维的直径越小，混杂效果越好；对于层间混杂，两种纤维的直径差异越大，则混杂的空隙率越小，而且树脂在整个复合材料中的分布越均匀，得到的复合材料的性能越好；采用DC88和T300混杂后复合材料的密度在1.12～1.24g／cm³之间，实现了预期的结构件减重的目的。更多还原

【Abstract】 The poor adhesion of non-polarity ultra-high molecular weight polyethylene (UHMWPE) fiber with commonly polar resin matrix limits its applications in structure composites. In order to improve adhesion of UHMWPE fiber with matrixs, three methods are explored in this work, which are UHMWPE fiber surface treatment, synthesizing VE resin and introducing carbon fiber to co-hybrid with UHMWPE fiber.The effects of chemical etching to the UHMWPE fiber’s surface chemistry and topography have been explored by using chromic acid. The best proportion of K2Cr:O7:H2O:H2SO4 is 10:16:140. The relationship between the treated temperature and the fiber’s tensile strength loss show that the best treated temperature is 85℃. Through SEM, FTIR. It has been proved that there are many oxy-organic groups appearing at the surface of treated UHMWPE fiber, including hydroxyl and carboxyl groups. The results of single fiber pull-out show that chemical etching on the surface can improve interface-adhesions between treated fiber and epoxy resin.The high performance VE resin has been obtained by methyl acrylic acid, epoxy E-51 polymerization with suitable proportion. The resin properties are characterized by FTIR, DMA, DTA, TGA, SEM. The research suggests VE has good thermal property, flexural property and impact property, what’s more, the adhesion with UHMWPE fiber is also excellent. VE resin can increase adhesion by 25 % in comparison to epoxy E-51.Carbon fiber T300 was chosen as a co-hybrid fiber, and two different kinds UHMWPE fiber/T300 hybrid composites are prepared in both inner-laminar and inter-laminar styles. The inter-laminar hybrid composites exhibited better adhesion than the inner-laminar ones. For the optimized system DC88/T300/VE, the ILSS reached 42.5MPa. 5 times of the untreated DC88/epoxy E-51 system. The density test suggested that the hybrid composite has a potential application. Three ideal hybrid models are proposed to study hybrid mechanisms on the basis of the adhesionproperty analyses by SEM.更多还原